What is the mesh the yellow arrow points to? The head?
Are the bumps circled in red the eyes and ear holes?
Overall, the normal map is sunken in or in other terms negative and smooth. I don’t see how this could be a benefit so I am not sure if it should even be used at all in this situation. Shouldn’t a skin diffuse map just be a seamless tiled texture? This looks like a loaded baked texture with maps made from it. I haven’t seen this before except when texture painting on an exported uv map that you will re import back into blender.
Maybe someone could explain this technique or show me a link to it with respect to pbr materials.
You add the gltf exporter to blender. Currently, this 2.79 version has two scripts, one for import one for export.
You use the glTF2_Principled.blend I linked to for appending the nodes. The other links show you how to setup and use the blender nodes as well as the art creation pipeline. Appending is as simple as having the blender node editor open and just appending from the file menu. For each material, you append a new node from the pricipled.blends material folder. It will populate with all the nodes above. Just rename the material and connect the links.
I tried to use the way you and others use but the script and the blender BSDF shader just wouldn’t work for me.
This is all included in the newly released Blender 2.8 beta and ready to use if you upgrade blender but that may open up a whole new can of worms.
2.8 may require relearning of things. Not sure yet myself.
As to the process. once the scripts are working, you just export to your project, convert the gltf to j3o and either add it into a project or open the j3o in SDK scene explorer. Best to open in SDK first so you can generate tangents for it if need be, check animations and get a quick idea if something failed along the way.
I have a project that is already configured for animations, movement and has a light probe that I use for experimentation so I load the j3o and play with it.
There is TestPBRLighting in the jme test classes you can use to setup your probe.
This is all real easy and fast once the tools are all configured. In materialize, you can pack textures.
Just click the buttons under Property Maps and set things up. You can then save that image and use it for your pbr setup in blender I showed above.
As long as you use the same image folder for gimp, blender and materialize, you are just reloading things after edits.
Edit in gimp and export, edit in materialize and save, reload with Blender textools, export to your project, convert and just run the project or open j3o in SDK scene explorer and run it from there.